Endothelial cells produce at least three substances that can attenuate the platelet aggregation response: tissue-type plasminogen activator; the platelet inhibitory prostaglandins I2 and E,; and endothelium-derived relaxing factor, one form of which exhibits properties of nitric oxide. Since platelet aggregates formed in vivo are involved in the initiation of many clinically important occlusive...

A unique characteristic of mammalian sperm thermotaxis is extreme temperature sensitivity, manifested by the capacity of spermatozoa to respond to temperature changes of <0.0006 °C as they swim their body-length distance. The identity of the sensing system that confers this exceptional sensitivity on spermatozoa is not known. Here we show that the temperature-sensing system of mammalian spermat...

Rule-based modeling is a new approach to cope with the inherent combinatorial complexity in protein-protein interaction networks, such as cellular signaling pathways. In contrast to reactions that act on chemical species, rules can act on partially specified species. A single rule can thus account for multiple reactions and reflects the limited local context on which most protein-protein intera...

Ribozymes are RNA molecules that act as chemical catalysts. In contemporary cells, most known ribozymes carry out phosphoryl transfer reactions. The nucleolytic ribozymes comprise a class of five structurally-distinct species that bring about site-specific cleavage by nucleophilic attack of the 2'-O on the adjacent 3'-P to form a cyclic 2',3'-phosphate. In general, they will also catalyse the r...

Endothelial cells produce at least three substances that can attenuate the platelet aggregation response: tissue-type plasminogen activator; the platelet inhibitory prostaglandins I2 and E1; and endothelium-derived relaxing factor, one form of which exhibits properties of nitric oxide. Since platelet aggregates formed in vivo are involved in the initiation of many clinically important occlusive...

the article introduces cyclic dilation groups and finite affine groups for prime integers, and  as an application of this theory it presents a unified group theoretical approach for the  cyclic wavelet transform (cwt) of prime dimensional periodic signals.

Integrin binding by Arg-Gly-Asp (RGD)-containing peptides has been shown to alter vascular tone in a variety of blood vessels and has been implicated as a mechanism of vasoregulation during tissue injury. However, the effect of these peptides in the coronary circulation has not been examined. Thus the purpose of our study was to test the hypothesis that integrins act as receptors linked to the ...

we present a 24-year-old female referred with non-healing wound of a few days duration on anterior aspect of her right foreleg. biopsy of the wound was reported to be pyoderma gangrenosum on pathologic report. further work up of the patient for high grade fever and occasional leukopenias revealed the diagnosis of cyclic neutropenia. treatment with granulocyte colony-stimulating factor (g-csf) r...